| 摘要 |
PURPOSE:To detect a fault generated on magnetic pole sensors for sensing clockwise and counter-clockwise rotations, and enhance the reliability, by arranging fault detecting circuits between comparators connected to the magnetic pole sensors, and a control section. CONSTITUTION:A driving circuit 10 is provided with a control circuit 11 for controlling the change-over of armature current. The control circuit 11 is provided with comparators 12-14 connected respectively to first magnetic pole sensors 4-6 for detecting clockwise rotation, and comparators 15-17 connected respectively to second magnetic pole sensors 7-9 for sensing counterclockwise rotation, and the respective comparators are connected to a common control section 20 via a first and a second fault detecting circuits 18, 19. When any fault of the first or the second magnetic pole sensors 4-6, 7-9 is detected by the fault detecting circuits 18, 19, with the control circuit 20, by using the output of the magnetic pole sensor on the normal side, the change-over control of the armature current is continuously performed. |
